1. Field of the Invention
The present invention relates to a capacitor and a method of manufacturing the same. More specifically, the present invention is directed to an improvement in a capacitor and a method of manufacturing the same, aimed at implementation in small size and/or with large capacitance.
2. Description of the Prior Art
A capacitor of interest to the present invention is one which employs ceramic as a dielectric material. In manufacturing such a capacitor, a ceramic dielectric material is prepared and formed with electrodes on both surfaces thereof so as to be opposed to each other or a plurality of ceramic green sheets having an electrode partially formed are laminated, whereupon they are fired to complete a capacitor.
One requirement in such capacitors is to implement them with a large capacitance. One means to attain large capacitance in such capacitor is to increase the area of the opposing electrodes; however, such means cannot be employed in applications where a capacitor need be small in size. Therefore, one might think of decreasing the distance between the opposing electrodes as a means for meeting both requirements of small size and large capacitance.
One means for decreasing the distance between the opposing electrodes would be to decrease the thickness of a ceramic serving as a dielectric in the case of a ceramic capacitor. However, in the case of a capacitor of a simple type wherein electrodes are formed on both surfaces of a ceramic dielectric material, there is a limitation to the amount the thickness of the dielectric material can be decreased and hence such an approach is not appropriate to obtain a capacitor of small size and large capacitance. On the other hand, in the case of a laminated capacitor having a plurality of ceramic green sheets, a laminated ceramic sheet is used as a dielectric material, which makes it possible to make the dielectric layer relatively thin. Nevertheless, there is still a limitation to the degree to which the thickness of the dielectric layer can be decreased in the case where a much thinner layer is required.
When using ceramic green sheets the minimum thickness thereof has been limited to several 10 to 100.mu. from the standpoint of handling thereof. More specifically, a decrease of the thickness of a ceramic green sheet to a value thinner than that decreases the mechanical strength of the sheets, which causes the sheet to be broken or damaged in handling, and hence a limitation to the minimum thickness is naturally determined.